In their comment ,Reference 1 Gupta and Sinha extend the analysis given by the authorsReference 2 of stimulated Brillouin scattering in a stationary plasma to a flowing plasma. The authors content that their formula including ion-temperature contribution is more accurate than that of Gupta and Sinha. (AIP)

Dwivedi’s claim [Phys. Plasmas 4, 3427 (1997)] that the dust-acoustic wave should not be viewed as a novel plasma wave is rebutted. The so-called acoustic-like mode introduced earlier by Dwivedi et al. [J. Plasma Phys. 41, 219 (1989)] rests physically on very dubious grounds, because it considers a plasma with two ion species in the presence of a fixed electron background. In addition, Dwivedi et al. have nowhere included heavy charged dust grains as potential applications of their (flawed) theoretical treatment. Hence Rao et al. (1990) were indisputably the first ones to point out the possibility of dust-acoustic modes, correctly so, as we argue, because a distinct name is fully justified by the enormous order-of-magnitude differences in the charge-to-mass ratios of the usual charged dust grains compared to “ordinary” ions and by the recent experimental verification.